1caab277bSThomas Gleixner/* SPDX-License-Identifier: GPL-2.0-only */ 20aea86a2SCatalin Marinas/* 30aea86a2SCatalin Marinas * Copyright (C) 2012 ARM Ltd. 40aea86a2SCatalin Marinas */ 50aea86a2SCatalin Marinas 60aea86a2SCatalin Marinas#include <linux/linkage.h> 7338d4f49SJames Morse 8b4b8664dSAl Viro#include <asm/asm-uaccess.h> 956c08ec5SMark Rutland#include <asm/assembler.h> 1056c08ec5SMark Rutland#include <asm/cache.h> 110aea86a2SCatalin Marinas 120aea86a2SCatalin Marinas/* 130aea86a2SCatalin Marinas * Copy from user space to a kernel buffer (alignment handled by the hardware) 140aea86a2SCatalin Marinas * 150aea86a2SCatalin Marinas * Parameters: 160aea86a2SCatalin Marinas * x0 - to 170aea86a2SCatalin Marinas * x1 - from 180aea86a2SCatalin Marinas * x2 - n 190aea86a2SCatalin Marinas * Returns: 200aea86a2SCatalin Marinas * x0 - bytes not copied 210aea86a2SCatalin Marinas */ 2240426882SFeng Kan 23ada66f18SCatalin Marinas .macro ldrb1 reg, ptr, val 247b90dc40SMark Rutland user_ldst 9998f, ldtrb, \reg, \ptr, \val 2540426882SFeng Kan .endm 2640426882SFeng Kan 27ada66f18SCatalin Marinas .macro strb1 reg, ptr, val 28ada66f18SCatalin Marinas strb \reg, [\ptr], \val 2940426882SFeng Kan .endm 3040426882SFeng Kan 31ada66f18SCatalin Marinas .macro ldrh1 reg, ptr, val 32*295cf156SRobin Murphy user_ldst 9997f, ldtrh, \reg, \ptr, \val 3340426882SFeng Kan .endm 3440426882SFeng Kan 35ada66f18SCatalin Marinas .macro strh1 reg, ptr, val 36ada66f18SCatalin Marinas strh \reg, [\ptr], \val 3740426882SFeng Kan .endm 3840426882SFeng Kan 39ada66f18SCatalin Marinas .macro ldr1 reg, ptr, val 40*295cf156SRobin Murphy user_ldst 9997f, ldtr, \reg, \ptr, \val 4140426882SFeng Kan .endm 4240426882SFeng Kan 43ada66f18SCatalin Marinas .macro str1 reg, ptr, val 44ada66f18SCatalin Marinas str \reg, [\ptr], \val 4540426882SFeng Kan .endm 4640426882SFeng Kan 47ada66f18SCatalin Marinas .macro ldp1 reg1, reg2, ptr, val 48*295cf156SRobin Murphy user_ldp 9997f, \reg1, \reg2, \ptr, \val 4940426882SFeng Kan .endm 5040426882SFeng Kan 51ada66f18SCatalin Marinas .macro stp1 reg1, reg2, ptr, val 52ada66f18SCatalin Marinas stp \reg1, \reg2, [\ptr], \val 5340426882SFeng Kan .endm 5440426882SFeng Kan 5540426882SFeng Kanend .req x5 56*295cf156SRobin Murphysrcin .req x15 573ac0f452SMark BrownSYM_FUNC_START(__arch_copy_from_user) 5840426882SFeng Kan add end, x0, x2 59*295cf156SRobin Murphy mov srcin, x1 6040426882SFeng Kan#include "copy_template.S" 6140426882SFeng Kan mov x0, #0 // Nothing to copy 620aea86a2SCatalin Marinas ret 633ac0f452SMark BrownSYM_FUNC_END(__arch_copy_from_user) 6456c08ec5SMark RutlandEXPORT_SYMBOL(__arch_copy_from_user) 650aea86a2SCatalin Marinas 660aea86a2SCatalin Marinas .section .fixup,"ax" 670aea86a2SCatalin Marinas .align 2 68*295cf156SRobin Murphy9997: cmp dst, dstin 69*295cf156SRobin Murphy b.ne 9998f 70*295cf156SRobin Murphy // Before being absolutely sure we couldn't copy anything, try harder 71*295cf156SRobin MurphyUSER(9998f, ldtrb tmp1w, [srcin]) 72*295cf156SRobin Murphy strb tmp1w, [dst], #1 734855bd25SAl Viro9998: sub x0, end, dst // bytes not copied 740aea86a2SCatalin Marinas ret 750aea86a2SCatalin Marinas .previous 76